1. Field of the Invention
The present invention relates to a data communications apparatus, a data communications system and a data communications method.
2. Description of the Related Art
From the past, there has been a data communications technique for establishing a communication between apparatuses in which an operator sets an identification number and an access condition for each apparatus. For example, in wireless LAN defined by IEEE802.11, the operator sets ESS-ID (Extended Service Set Identifier) for each apparatus so that communications are established among apparatuses having the same ESS-ID for sending and receiving data among the apparatuses. Therefore, when an apparatus is newly connected to an existing network, it is necessary for the operator to check beforehand identification numbers such as ESS-IDs and access conditions of apparatuses already connected to the network.
By the way, as defined in the IEEE802.11, ESS-ID of an apparatus already connected to a network can be obtained by setting “ESS-ID” to be “ANY”. Thus, there is an apparatus that displays a list of apparatuses to which the apparatus can connect on a display device of the apparatus when there are a plurality of apparatuses having different ESS-IDs. The operator selects an apparatus from the list for establishing a connection to the selected apparatus.
The list displayed by the apparatus includes ESS-IDs of each apparatus or names of each apparatus on the network or the like. Thus, it is necessary to manage correspondences between actual apparatuses and the names or the like on the network, and to compare the names or the like displayed on the list with the actual apparatuses for designating an apparatus connection. Therefore, a complicated procedure is required.
In addition, since ESS-IDs of connectable apparatuses can be obtained by setting ESS-ID of an apparatus that will connect to the network to be “ANY”, a third party can access apparatuses easily so that there is a problem in that it becomes difficult to ensure security by performing access control. Following documents may relate to this application.                [Patent Document 1] Japanese Laid-Open Patent Application No. 2005-159821        [Non-Patent Document 1] Ken Hinckley (Microsoft Research), “Synchronous Gestures for Multiple Persons and Computers”, Nov. 4, 2003, UIST2003 (Annual ACM (Association for Computing Machinery) Symposium on User Interface Software and Technology 2003).        
The patent document 1 discloses a communications apparatus for communicating with another apparatus. The communications apparatus obtains, from each of a plurality of communications apparatuses that is a candidate of a communication destination, movement information indicating movements in a space of the communications apparatuses, and displays the movement information. The user selects one of displayed movement images so that the communication apparatus communicates with a communication apparatus indicated by the selected movement image.
The non-patent document 1 discloses tablet PCs each having a multiaxial acceleration sensor. The tablet PC is a personal computer including a wireless communication unit and a pen inputting unit, and is small so as to be carried easily. The acceleration sensor detects contact with another tablet PC and direction of the contact so that each tablet PC changes content form displayed on a screen of the tablet PC.
However, as to the communications apparatus disclosed in the patent document 1, since the operator selects another communications apparatus to communicate with based on the movement information of the plurality of communications apparatuses each being a candidate of a communication destination, the operator needs to visually compare movement of the communications apparatuses in an actual space with movement information displayed on the screen.
In addition, according to the tablet PC disclosed in the non-patent document 1, the acceleration sensor is used for controlling application and the like among tablet PCs in which communications are already established. But, it is not considered to establish a communication or to perform communication control such as access control.